It seems that installing PyQt4 is not a trivial task for users particularly on MacOS system.
To handle this problem, you may refer to https://pythonschool.net/pyqt/installing-pyqt-on-mac-os-x
Or http://www.noktec.be/python/how-to-install-pyqt4-on-osx, but please keep in mind in BioNanoAnalyst, it uses python 2 instead of python3.
Another solution can be found here: http://stackoverflow.com/questions/36615952/how-can-i-install-pyqt4-for-python-2-7.
If you still fail to install PyQt4 in your MacOS system. You may try to install such as Canopy (https://www.enthought.com/products/canopy/) and use its package manager to install PyQt4 or Pyside.
It seems that installing PyQt4 is not a trivial task for users particularly on MacOS system.
To handle this problem, you may refer to https://pythonschool.net/pyqt/installing-pyqt-on-mac-os-x
Or http://www.noktec.be/python/how-to-install-pyqt4-on-osx, but please keep in mind in BioNanoAnalyst, it uses python 2 instead of python3.
Another solution can be found here: http://stackoverflow.com/questions/36615952/how-can-i-install-pyqt4-for-python-2-7.
If you still fail to install PyQt4 in your MacOS system. You may try to install such as Canopy (https://www.enthought.com/products/canopy/) and use its package manager to install PyQt4 or Pyside.